PowerBird 900 W can really deliver its labeled power at 50º C, which is excellent. It also delivers high efficiency between 83.7% and 85.6% if you pull up to 80% of its load (i.e. up to 720 W). At full load efficiency was still above 80%, at 81.1%.

Noise and ripple were low and the main voltages were within 3% their nominal value, as promised by the manufacturer (tighter than the official standard, which states a 5% tolerance).

The fully modularized cabling system is a must for the high-end user that wants to have only the cables he (or she) will be really using, making things more organized inside the case and improving airflow.

It also supports three-way SLI directly, which is desired by its targeted audience.

This is an excellent buy for the high-end user. Although officially quoted at USD 250 it can be found for USD 180 at Newegg.com, which isn’t a bad price at all for a true 900 W power supply.

Many people are still asking why manufacturers sell high-wattage power supplies if even fully loaded PCs with three or four video cards don’t pull even close to 900 W. The answer lies on efficiency. Power supplies present their highest efficiency when delivering between 40% and 60% from their labeled power. Thus by buying a power supply labeled at double the actual power pulled by the system you are making sure that you are getting the best efficiency and this way saving on your electricity bill. For more information on this, please read our Everything You Need to Know About Power Supplies tutorial.